Arterial hypertension induced by femoral lengthening. A canine model.

In a canine experimental model, femora were lengthened 2.5 to 3.0 centimeters over a one-minute period. Systolic blood-pressure elevation averaged forty millimeters of mercury and diastolic blood-pressure elevation, twenty-two millimeters of mercury. The average peak arterial pressure was 193/115 millimeters of mercury. The effects of sympatholytic agents on the experimental model were tested. Alpha-adrenergic blockade by phenoxybenzamine, total-body catecholamine depletion by reserpine, and sympathetic ganglionic blockade by trimethaphan camphorsulfonate all inhibited the rise in arterial pressure, but beta-adrenergic blockade by propranolol did not. A differential spinal anesthetic with Xylocaine solution dramatically decreased the elevation in arterial pressure.